A. Field
The present invention concerns a construction element, in particular a construction element for forming a reinforced concrete slab, as well as a method for manufacturing such a construction element.
B. Related Art
In particular, it concerns a construction element of the type which consists of the combination of at least a hardened concrete layer, at least a number of reinforcement elements and elements extending at least partially from the concrete layer and defining cavities, whereby these elements are designed to be covered with concrete in the factory or on the building site at a later stage.
With the known embodiments of this type of construction elements, use has been made until now of spherical elements for the cavities, in particular balls or the like, which are slightly embedded at the bottom in the concrete layer and are moreover kept in place by means of mutually connected reinforcement nets, a first reinforcement net situated under the spherical elements in the concrete layer and a second reinforcement net extending above the spherical elements respectively. The second reinforcement net is hereby meant to keep the spherical elements in place, in particular to lock them against floating at the time when liquid concrete is poured over it.
These known embodiments have several disadvantages.
The hollow spherical elements, which are usually manufactured in another place than the construction elements themselves, result in high transport costs, as they occupy a relatively large volume, although they have a low weight. Another disadvantage consists in that these spherical elements are difficult to manipulate, especially in an automated process.
Another disadvantage of these known embodiments consists in that their manufacture is rather complex, as the construction element as such already has to be provided with a top reinforcement net, which moreover preferably has to be provided on it in a very precise manner in order to make sure that the spherical elements are locked in the required positions.
Another disadvantage of these known embodiments consists in that the spherical elements rest against the top reinforcement net or can make contact with it as a result of floating, so that, after the liquid concrete has been poured over the construction element, the top reinforcement net cannot be optimally embedded in the concrete. In practice, this can be remedied by making use of separate locking elements which are connected to the top side of the spherical elements in order to prevent the spherical elements from floating, but this is disadvantageous in that the construction as a whole becomes complex and time-consuming.
Also, the present invention aims a construction-element of the aforesaid type, whereby one or several of the above-mentioned disadvantages are excluded.